Business overview-


  • Conversion Coating

    We liberate metal from rust! Nihon Parkerizing Co., Ltd. was established in 1928 with the introduction of the Parkerizing method of phosphating treatment of steel from Parker Rust Proof Company. Nihon Parkerizing's conversion coating treatments, including our representative phosphating treatment, have become core technologies for multi-functional products and include paint bases, lubricant bases, wear resistant applications for sliding parts, bases for adhesive bonding and applications for cold forming. We will continue to utilize our original technology to satisfy a diverse range of needs.

  • Rubricant for deformation

    Chemical bonding enables the maintenance of a strong lubricant layer for cold forming.

  • Solid Lubricant Coating

    We offer an extensive range of metal hardening treatments from the conventional to the very latest metal hardening treatments.

  • Rust Proof Coating

    A combination of conversion coating and resin coating provides corrosion resistance in addition to other functions.

  • Salt-Bath Nitriding

    Nihon Parkerizing's original surface hardening method, ISONITE, dramatically improves the characteristics of a variety of ferrous metals.

  • Salt-Bath Carburizing

    Salt-bath carburizing is a unique treatment method for achieving hardening of steel with no distortion or cracks.

  • AUSTEMPER treatment

    AUSTEMPER treatment promises to not only improve characteristics but also create a beautiful finish with minimal dimensional change.

  • Composit Plating

    Functional particles are dispersed in the plating bath and made to disperse in the metal matrix.
    When combined with heat treatment, the corrosion resistance, thermal resistance and wear resistance characteristics can be further strengthened.

  • Plasma Electrolytic Oxidation(PEO)

    This product forms an extremely hard ceramic film on light metals.
    Characteristics: high degree of hardness, exceptional wear resistance, high corrosion resistance, high thermal resistance.


    The use of bare weathering steel first became widespread in the U.S. due to the cost advantage and attractive appearance of rust. However, in Japan, where rainfall is high and the climate can be hot and humid, the initial rust outflow and rust dust caused significant pollution in the vicinity of the structures. Furthermore, it was difficult to form a stable rust layer on parts where ventilation was poor or there was frequent condensation, significantly limiting the use of bare weathering steel. As a manufacturer of metal surface treatments, Nihon Parkerizing took up the challenge to solve these problems with our surface treatment technology by developing the WEATHERCOAT method for developing a stable rust layer on weathering steel, in collaboration with Nippon Steel Corporation.